1. Field of the Invention
Embodiments of the present invention relate to methods, media, and apparatuses controlling a handover, and more particularly, to methods, media, and apparatuses controlling a handover, without deteriorating the quality of data transceived when the handover is performed between different network types.
2. Description of the Related Art
In recent years, the number of wireless Internet users has increased due to the rapid spread of the Internet, the development of wireless communication technology, and performance enhancements in mobile terminals such as a portable computer and a personal digital assistant (PDA). A mobile terminal may frequently travel from network access points within a wireless Internet environment.
To enable the mobile terminal to perform wireless Internet communication, an Internet service having the same high quality as that of a current network environment should be ensured even when the mobile terminal moves from a current network area to another network area. In other words, the mobile terminal should perform seamless communication. That is why the handover is derived therefrom, which means a function of transferring a communication procedure from an access point (hereinafter, it will be referred to as AP) in the current network area to an AP in the next network area. An Inter-Access Point Protocol (IAPP) for communication and handover between APs is defined by the Institute of Electrical and Electronics Engineers (IEEE).
In the meantime, real time multimedia services, including Video On Demand (VOD), Audio On Demand (AOD), picture phones, video chatting, and so forth have become popular due to recent Internet developments. In particular, such services have become popular due recent wireless Internet developments and enhancements in processing powers, real time multimedia services using the mobile terminal have been enabled, and associated markets are rapidly growing.
By way of the above-mentioned technology developments, it has been possible for a user to move while receiving real time multimedia services through his/her mobile terminal. As a result, this movement is followed by a handover of the mobile terminal to the next AP. Accordingly, much research has been conducted on control methods capable of effectively performing the handover.
Conventionally, when the mobile terminal performed the handover, the difference between a previous transmission Band Width (BW) supported by a previous network, e.g., before movement of the mobile terminal, and a transmission BW supported by a current network terminal was not considered. As a result, when the transmission BW supported by the previous network is larger than that supported by the current network, after movement, loss of data packets was not compensated for due to the difference of the transmission BWs, which causes the quality of the real time multimedia service to be deteriorated.
For example, assuming that the previous network, before movement, is a Wireless Local Area Network (WLAN), and the current network after movement is a 3 Generation Partnership Project (3GPP) wireless network, the WLAN area supports 384 Kbps as the transmission BW, while the 3GPP wireless network area supports 144 Kbps as the transmission BW. When the user moves from the WLAN area to the 3GPP wireless network area, while receiving the real time multimedia, service through his/her own mobile terminal under these environments, there occurs a transmission BW difference. As a result, the quality of the real time multimedia service deteriorates.